Electrocardiographic artifact.

Electrocardiographic (ECG) artifact, a common nuisance, has a wide range of manifestations with varying clinical significance. Beyond loose leads, motion artifacts and broken wires, artifact can also be caused by external and implanted devices as well as by physiologic signals. ECG artifact can mimic a variety of serious clinical conditions and arrhythmias such as acute myocardial infarction and ventricular tachycardia. The purpose of this review is to provide a structured approach to the recognition of the different forms of ECG artifact and to offer simple and practical steps to avoid misdiagnoses caused by artifact. Special attention is given to artifact whose presence can actually aid in the diagnosis of important and sometimes critical clinical conditions.